New medications for treatment of opioid dependence have been recently approved (LAAM) or are currently under consideration for approval (buprenorphine) by FDA. Both are long-acting; buprenorphine may be unique in having a high safety profile, and limited physical dependence. Both may be useful in detoxification treatment. However, there is currently insufficient information concerning the syndrome associated with withdrawal from LAAM and buprenorphine and no systematic, well-designed, well-controlled studies comparing LAAM, buprenorphine and methadone detoxification have been conducted. Two complementary studies are proposed: 1) a residual laboratory comparison of withdrawal syndromes following abrupt discontinuation of LAAM, buprenorphine and methadone and 2) an outpatient comparison study of LAAM, buprenorphine and methadone in detoxification treatment. The first study will utilize the controlled environment of the residual research unit to obtain a detailed assessment of time course, intensity and symptom profiles during spontaneous withdrawal from methadone, LAAM and buprenorphine. Two methadone doses (30, 100 mg/day) will be included to provide relevant benchmark comparison data. The second study will assess the comparative efficacy of the three medications in outpatient detoxifications during short (10 day) and longer-term (50 day) dose tapering schedules similar to those used in non- research treatment services. A methadone maintenance conditions will provide relevant comparison data for interpreting observed withdrawal symptomatology. Both studies will utilize rigorous and proven clinical trials methodology to obtain scientifically useful data directly comparing the characteristic opioid withdrawal syndromes associated with LAAM, buprenorphine and methadone. Further, with the approval of LAAM and buprenorphine as treatment medications for opioid dependence, these studies will provide the information needed by clinicians for medications and dose selection in detoxification treatment as well as optimal dose reduction schedules for LAAM and buprenorphine.